The influence of fly ash morphology and phase distribution on collection in an electrostatic precipitator

Fly Ash is the unburnt portion of fuels which is carried away as solid particles in the hot gas stream of a furnace. About 99% of the fly ash produced in a typical coal-fired power station is removed by electrostatic precipitators or baghouse filters located at the base of the emission stack. Precipitator efficiency is dependent on the charging properties of the fly ash particles and the adhesive forces between them. These forces depend on the size, morphology, chemical constitution and phase distribution of the fly ash. Larger particles are usually found as aggregates held together by bridging material which may be small glassy particles, graphite sheets, or a mixture of amorphous material and small crystallites.